Bush TR130 inoperative

[telstar]

Hi. I managed to complete the repair of my Bush TR130 transistor radio for Easter. It has the Luxembourg Band spread.
The original problem was that the battery leads had age hardened, the clips were loose, and if you tried to add extensions to the original wire, they did not join very well. The original leads were also a bit short in length.
I put some new wires in place, but also there was a bit of disturbance to the adjacent wires due to releasing wire clips. Some of the thinner wires came off the board and had to be rewired.
One of the electrolytic capacitors from the negative supply rail to chassis (positive) was pulling the voltage down to about 5 volts, it should have been 7.5 volts. This capacitor was nearer the r.f side of the radio. Once this was replaced with a 100 uF the stations came back.
Unfortunately the pointer came off its carriage and ended up being broken during trying to get the new battery leads wired to the switch, as I had to work in an awkward situation. Fortunately, I sorted this out by visiting a model shop in east Leeds and buying some cement used in joining plastic. This joined the pointer together.
The volume control is beyond service as it crackles, and would require replacing.
The battery terminal hood just requires some cosmetic work as it has been ripped. It just requires some glue at one end.
The carriage for the pointer no longer fouls the mechanism on the chassis.

The earphone socket got damaged before all this, so I did the necessary wiring change.
I had this working by Easter Sunday and listened to Radio Caroline's 58th anniversary.

[wd40addict]

Have you tried squirting some servisol in the volume control?

[Hybrid tellies]

Now you mention it I can remember mention of this problem with those rubber mounts. I think they can be replaced without dismantling the dial drive but it is a bit fiddly due to lack of space.
You might be able to affect, or should that be effect, a repair on the dial pointer.

[telstar]

Originally Posted by Hybrid tellies

Now you mention it I can remember mention of this problem with those rubber mounts. I think they can be replaced without dismantling the dial drive but it is a bit fiddly due to lack of space.
You might be able to affect, or should that be effect, a repair on the dial pointer.

Many thanks for your reply. The dial pointer has been repaired using liquid cement (like Airfix adhesive). I see how it has been assembled now with the wedge shaped item across the carriage that rides above the drive cord, and of course the pointer fits through the hole.
The rubber mounts have gone quite bad.

[telstar]

Originally Posted by wd40addict

Have you tried squirting some servisol in the volume control?

Yes I have tried some Servisol in the volume control, the results are only temporary

[Hybrid tellies]

Hopefully you may find replacement rubber mounts on line or possibly a good hardware shop. Regards the volume control if it’s noisy and switch cleaner doesn’t work it could be the capacitor feeding the audio amp gone leaky which will introduce dc onto the track and make it noisy.

[AD360 Rob]

You can use a 3/8" grommet for the tuning capacitor rubber mounts, it's a fiddly job but worth the effort.
Make sure to buy rubber rather than the shiny soft plastic ones.

[telstar]

Originally Posted by Hybrid tellies

Hopefully you may find replacement rubber mounts on line or possibly a good hardware shop. Regards the volume control if it’s noisy and switch cleaner doesn’t work it could be the capacitor feeding the audio amp gone leaky which will introduce dc onto the track and make it noisy.

Hi. I have tried changing the capacitor. It did not solve the problem.

[Hybrid tellies]

In that case it's a replacement that is required. I changed the volume control on my TR130 a few years ago which solved a similar issue. It's a bit fiddly but well worth while.
Also whilst you are there check and clean the gear wheels which can cause problems with broken teeth if they become stiff.

[David G4EBT]

Originally Posted by Hybrid tellies

Hopefully you may find replacement rubber mounts on line or possibly a good hardware shop. Regards the volume control if it’s noisy and switch cleaner doesn’t work it could be the capacitor feeding the audio amp gone leaky which will introduce dc onto the track and make it noisy.

I don't know if the TR130 rubber suspension mounts are the same dimensions as the Bush TR82s. If so, when searching for grommets online to act as suitable replacements, the following comments and attached sketches might be of help, which also explain how suppliers quote the five dimensions 'A' to 'E' when specifying grommets.

Most grommets are designed to simply fit a hole to prevent cables from being cut into by sharp metal edges on electrical boxes. When used as suspension mounts on Bush TR82s they're being use for is a different purpose so the 'bulbous' ends need to be thick enough to stop the capacitor wobbling about.

The critical dimensions of grommets to replace the rubber mounts on the tuning capacitor are that the brass spacer inside the grommet in the TR82 is 6.2mm long. That ensures that when the securing screw is tightened, the screw doesn't foul the tuning capacitor vanes. The outside diameter of the spacer is 5.5mm so the hole in the centre of the grommet needs to be no more than 6mm. When tightened, the gap between the mounting bracket of the tuning cap and the tuning cap frame is 2.75mm, so the thickness of the rims of the grommet need to be at least 3mm so that then the mounting screw is tightened, the tuning cap won't wobble about, which is the problem we're seeking to resolve.

This all sounds a bit obscure without reference to the sketch and with the chassis in front of you.

I mentioned this topic in post #17 of the thread below, highlighting grommets which I felt would fit the bill, (presently 17.6p each), but unfortunately, they're in bags of 100, which rather rules them out, but the sketches of the dimensions might be useful in sourcing suitable grommets from other suppliers.

https://www.vintage-radio.net/forum/...d.php?t=179664

I hope this has some relevance to the TR130 mounting bushes and is of interest.